Chemical cleaners are a significant portion of the industrial cleaning market. A chemical cleaner is typically aqueous and comprises an organic solvent to solubilize various soils, a surfactant, which serves as a wetting agent, and a builder, which serves to chelate ions present in water, such as magnesium and calcium. The types and ratios of these ingredients can vary considerably depending on the types of soils to be cleaned and the performance desired. It is common that all components are water-soluble.
In some instances, however, particularly with the solvent ingredient, the water solubility can be negligible. In these cases, components commonly called “couplers” or “hydrotropes” are used to increase the apparent water solubility of the organic solvent in the cleaning composition. The amount of coupler required depends on the type of coupler, organic solvent, and the other components of the mixture. It is typically preferred to use the minimum amount of coupler necessary to completely solubilize the solvent, as this tends to reduce the cost of the cleaning composition.
It is well known that removing hydrocarbon-containing soils from surfaces can be extremely difficult. These hydrocarbon-containing soils may include industrial type greases such as motor oil and lithium grease, and food greases such as lard and vegetable oils, as well as a wide range of other oily, greasy materials. The goal of formulating a cleaning composition that will effectively remove greasy residues from a hard surface has lead to a bewildering array of cleaning compositions on the industrial market. In general, the user wishes to achieve fast cleaning using the least amount of cleaning composition possible to avoid leaving behind residual chemical on the surface being cleaned.
There have been attempts to make improved cleaning compositions. They have included compositions providing improved cleaning that were substantially non-streaking on hard surfaces and contain a surfactant of amine oxide and a quaternary amine salt and a slightly polar organic compound. These cleaning solutions are effective for food soils, grease and the like.
Another class of cleaning compositions are those capable of removing hydrophobic soils, such as food grease and the like are those containing a non-ionic surfactant, and a very slightly water soluble organic solvent.
Although many commercially available cleaning compositions are quite effective at cleaning food grease, and others, particularly solvent-based cleaning compositions, are quite effective at removing industrial grease, the development of a cleaning composition that is effective in removing both food and industrial grease has been particularly challenging. Users are always desirous of improved grease removal properties in cleaning compositions, especially those that are capable of penetrating and emulsifying the soil quickly.